The stated overall objective of the project is to further understand the interaction of the physical and biochemical factors governing the maintenance of a normal lens cation transport system and the changes that occur with cataract formation. Goals set forth for the current year include completion of studies of electrolyte content and hydration data begun on cetylpyridinium chloride (CPC) -- induced cataracts, triparanol-induced cataracts, and human senile cataracts. In addition, work will be begun on the effect of various vitrectomy infusion fluids on cataract formation and lens electrolyte balance to be described in the body of the grant. THE RESEARCH GOALS INCLUDE: a) Completion of section described in section 2 C. b) Initiation of studies described in section 2 E. BIBLIOGRAPHIC REFERENCES: Peyman, G.A., Fishman, G.A., Sanders, D.R., Apple, D.J., and Vlchek, J.K.: Biopsy of human scleral-chorioretinal tissue. Invest. Ophthalmol. 14: 707-710, 1975. Sanders, D.R., Peyman, G.A., Fishman, G., and Korey, M.: Toxicity of intravitreal whole blood and hemoglobin. Albrecht von Graefe's Arch. Klin. Exp. Ophthalmol. 197: 255-267, 1975.